Hoist



May 22,1923. 1,456,131

D. P. KARCHER' HOIST Filed Dec 2'1 1920 Patented may 22, 19233..

' insane are set,

DAVID PERCY KARCHER, OF SOIVIERTILLEL IYIASSACHUSETTS.

, PCOIST.

Application filed December 21, 1926.

To all reliant it may concern:

Be it known that 1, DAVID PERCY Planer-Inn, a citizen of the United States, residing at Somerville, in the county of Middlesex and State of Massachusetts, have invented certain Improvements in Hoists, of which the following description, in connection with the accompanying drawings, is a specification, like reference characters on the drawings indicating like parts .in the several figures. I

This invention relates to hoisting mechanisms of the type commonly known as whip hoists.

It is the chief object of the invention to devise a hoisting mechanism of this type which, while havingthe simplicity of construction, convenience of operation and other advantages of the usual whip hoists, shall be more reliable than prior constructions, shall be capable of rendering greater length of service without requiring repair or replacement of parts, and which generally shall be an improvement on prior mecha nisms of this character.

The nature of the invention will be readily understood from the following description when read in connection with the accompanying drawings, and the novel features will be particularly pointed out in the appended claim.

Referring now to the drawings,

Figure 1 is a side elevation of a hoisting mechanism constructed in accordance with the present invention, certain parts being broken away, however;

Fig. 2 is a plan View of the mechanism) shown in Fig. 1; and i 3 is a cross sectional view on the line 3-3, Fig. 1.

The construction shown comprises a frame consisting of a bed 2 and side pieces 3 and f supported on the bed. A hoisting drum 5 is secured fast to a wheel 6 and these parts are rotatably mounted on a relatively stationary shaft 7. The wheel 6 is driven by a friction roll 8 fast on a shaft 9 which is supported in bearings 10 and 11 mounted, respectively, in the opposite side pieces 3 and 4: of the frame, the bearing 11 which receives the heaviest duty preferably being of the roller type. A gear 12 is mounted fast on the shaft 9 and is driven by a pinion 13 fast on the shaft of an electric motor 14, this motor being mounted. on the bed 2.

Serial No. 432,174.

Any other suitable means for driving the shaft 9 may, however, be employed.

. At a point remote from the friction roll 8, and preferably diametrically opposite therefrom, is mount-ed a brake shoe 15, this shoe being mounted on a transverse rod 16 supported in slots formedin the opposite side members 3 ands: of the frame. Adjusting screws 1717 bear against this rod and afford a convenient means for effecting an accurate adjustment of the brake shoe relatively to the wheel 6.

The drum shaft 7 is supported at opposite sides of the hoisting drum in a pair of double eccentrics. The construction at the forward end of the shaft is clearly illustrated in Figs. 1 and 3 and this construction is duplicated at the opposite end. Referring to these two figures it will be seen that the end ofv the shaft is supported in an inner eccentric 20 and that this eccentric is rotatably mounted in an outer eccentric 21. The latter eccentric is located in an aperture formed for it in the side piece 3 of the frame. This eccentric. is normally stationary and is provided with a peripheral flange 22, Fig. 3, which overlies the face oftheframe piece 3 and has a series of holes 23 drilled therethrough to receive bolts 24 by means of which the outer eccentric may be secured in any desired position of angular adjustment.

The inner eccentric 20 is free to rock or rotate within the outer eccentric 21 and this rocking motion is produced by a controlling lever 25 which is bolted both to theeccentrio and also to the end of the shaft 7. A rope or chain 26 is connected with the end of this lever through suitable sheaves to raise the lever, and a weight 28 adjustably mounted on this lever normally holds it in its lower position.

As above stated the construction at the rearward end of the shaft 7 is like that at the forward end. ,There is, however. no controlling lever at the rearward end of the shaft, but a short piece 29 is bolted to the inner eccentric and the shaft and secures these parts together so that they must rotate in unison.

It will now be evident that normally the weight 28 acting on the lever 25 operates tl'irough the inner eccentrics and the shaft 7 to hold the wheel 6 against the brake shoe 15 and thereby retains the d rum 5 and wheel 6 normally at rest.

WVhen the free end of the lever 25 is raised by pulling on the rope 26 the rotative movement thereby imparted to the inner eccentrics carries the shaft 7 bodily toward the left, Fig. 1, thus moving the wheel 6 into engage'ment with the friction roll 8 and simultaneously carrying the wheel out of engage-- ment with the brake shoe 15. Assuming that the roll 8 is being driven at this time by the motor 1 1 the result will be-to drive the wheel 6 and drum 5 so long as the parts are retained in this relationship. In order to interrupt this driving engagement and to bring the drum'to rest again, it is merely necessary to release the rope 26, when the v weight 528 will bring the parts back into the positions in which they are shown in Fig, 1.

It is evident that the surfaces of the friction roll 8 and the wheel 6 will gradually wear down, the surface of the roll 8 wearing more rapidly than that of the wheel.

The eccentric mounting of the shaft 7 vor 7 course will take care of considerable wear,

but in. order to compensate for additional wear the second pair of eccentrics has been provided. That is, when the friction surfaces of the parts 6 and 8 have worn so much that the throw of the controlling lever has become excessive, or the driving engagement of'the roll 'SWltll the wheel 6 impaired,,it is merelynecessary to remove the bolts 2a 2i from the flange of the outer eccentrics and turn these eccentrics oneor two holes counter-clockwise direction, referring to Fig. l, and thenreplace thebolts.

This'operation has the effect of adjusting the Wheel 6 and drum 5 bodily toward the left, Fig. l, and thus brings the driving wheel closer to the friction roll 8 and therefore compensates for the wear on the surfaces of these two parts. irt the same time the adjusting bolt 1717 should be moved inwardly to move the brake shoe15 somewhat closer to the periphery of the wheel 6. The hoist then will. operate as satisfactorily 'as when new. This adjustment to compensate for wear, inaddition to being simple and easy for the workman or mechanic to operate, also has the advantage of being ecothe inachine'contribut'es very materially to friction roll mounted to engage the periphfj cry of said wheel to drive said wheel and drum, a shaft supporting said roll, bearings supporting said'shaft at opposite sides of the .point of engagement of said roll with said' wheeL a. brake shoe mounted to engage the periphery of said wheelat a point remote from the engagement therewith of said roll, a relatively stationary shaft on which said drum and wheel are rotatably mounted,

two eccentrics secured to said stationary shaft at opposite sides of saiddruin and supporting said shaft, two additionaleccentrics within which, respectively, the, first eccentrics are mounteth'a frame in which said additional eccentrics are supported, for angular adjustment, means for securing said additional eccentrics in various positions of angular adjustment, and an operating lever secured to said shaftto rock saidsliaft and the eccentrics secured thereto relatively to the second pairof eccentrics, whereby said rocking movement will effect a bodily transfer of said drum and said roll and brake;

In testimony whereof I have signed my name to this specification.

DAVID PERCY KARoi-inn,

wheel toward or from 

